C# 实现图片随便裁剪以及羽化功能,在线坐等大神.

C# 实现图片任意裁剪以及羽化功能,在线坐等大神.........急急急急急急.......
C# 实现图片任意裁剪以及羽化功能
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/// <summary>
        /// 剪裁 -- 用GDI+
        /// </summary>
        /// <param name="b">原始Bitmap</param>
        /// <param name="StartX">开始坐标X</param>
        /// <param name="StartY">开始坐标Y</param>
        /// <param name="iWidth">宽度</param>
        /// <param name="iHeight">高度</param>
        /// <returns>剪裁后的Bitmap</returns>
        public static Bitmap CutImage(Bitmap b, int StartX, int StartY, int iWidth, int iHeight)
        {
            if (b == null)
            {
                return null;
            }

            int w = b.Width;
            int h = b.Height;

            if (StartX >= w 
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 StartY >= h)
            {
                return null;
            }

            if (StartX + iWidth > w)
            {
                iWidth = w - StartX;
            }

            if (StartY + iHeight > h)
            {
                iHeight = h - StartY;
            }

            try
            {
                Bitmap bmpOut = new Bitmap(iWidth, iHeight, PixelFormat.Format24bppRgb);

                Graphics g = Graphics.FromImage(bmpOut);
                g.DrawImage(b, new Rectangle(0, 0, iWidth, iHeight), new Rectangle(StartX, StartY, iWidth, iHeight), GraphicsUnit.Pixel);
                g.Dispose();

                return bmpOut;
            }
            catch
            {
                return null;
            }
        }
    }

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图片在线裁剪示例
<script type="text/javascript">
    $(function() { $('#oImage').Jcrop({ boxWidth: 520, boxHeight: 330, onChange: showCoords, onSelect: showCoords }); }); //当选择、改变选区时都执行showCoords函数
    function showCoords(c) {
        $("#txtX").val(c.x);//得到选中区域左上角横坐标
        $("#txtY").val(c.y);//得到选中区域左上角纵坐标
        $("#txtW").val(c.w);//得到选中区域的宽度
        $("#txtH").val(c.h); //得到选中区域的高度
    }//codego.net/
    function checkCoords() {
        var defaulturl=document.getElementById("oImage").src;
        defaulturl=defaulturl.substring(defaulturl.lastIndexOf("/")+1);
        if (defaulturl == "default1.jpg") {
            alert("请上传图片");
            return false;
        }
        else {
            if (parseInt($('#txtH').val()) && parseInt($('#txtW').val())) {
                sendImg();
                return true;
            }
            else {
                alert("请设置裁剪区域");
                return false;
            }
        }
    };
    function sendImg() {
                var p = document.getElementById("oImage").src;
                var x = document.getElementById("txtX").value;
                var y = document.getElementById("txtY").value;
                var w = document.getElementById("txtW").value;
                var h = document.getElementById("txtH").value;
                var ow = 222;
                var oh = 300;
                var rate = w / h;
                if (rate > 1)//选区的宽大于高
                {
                    document.getElementById("imgCreat").width = ow;
                    document.getElementById("imgCreat").height = ow / rate;
                }
                else if (rate < 1) //选区的高大于宽
                {
                    document.getElementById("imgCreat").width = oh * rate;
                    document.getElementById("imgCreat").height = oh;
                }
                else if (rate == 1) {
                    document.getElementById("imgCreat").width = 222;
                    document.getElementById("imgCreat").height =222;
                }
                document.getElementById("imgCreat").src = "Handler.ashx?p=" + p + "&x=" + x + "&y=" + y + "&w=" + w + "&h=" + h + "&" + Math.random();
            }
        </script>